Monoclonal antibodies that recognize the product controlled by a gene in the I-J subregion of the mouse H-2 complex.

The B cell hybridomas producing monoclonal antibodies (E10, D7, F4, H6, and D4) were established by the fusion of P3U1 or NS-1 murine myeloma cell lines and spleen cells of B10.A(5R) mice hyperimmunized with mitomycin C-treated B10.A(3R) spleen and thymus cells. Two types of monoclonal antibodies specific for the products controlled by a gene in the I-Jb subregion of the H-2 complex were characterized: one specific for the private type of I-Jb determinant, the other recognizing the cross-reactive determinant between the I-Jb and I-Jd products. By using these monoclonal reagents, the I-J-encoded product on the antigen-specific suppressor T cells was found to be expressed on their soluble suppressor factors. Furthermore, the I-Jb products were successfully detected not only on the T cell hybridoma with suppressor activity specific for keyhole limpet hemocyanin (KLH), but also on KLH-primed suppressor T cells enriched by antigen-coated petri dishes and concanavalin A-induced thymocyte blasts of C57BL/6 mice by complement-dependent cytotoxic assays and membrane fluorescence techniques.